Abstract base model testing classes for pytest and Django

model_base_classes.py

from django.db import models

import pytest

DATETIME_FIELDS = (models.DateTimeField, models.DateField, models.TimeField)


class BaseModelTest:
    model: models.Model = None

    def test_issubclass_model(self):
        assert issubclass(self.model, models.Model)


class BaseModelFieldTest:
    model: models.Model = None
    field_name: str = None

    field_type: models.Field = None
    is_null: bool = False
    is_blank: bool = False
    default_value = models.fields.NOT_PROVIDED

    is_auto_now: bool = True
    is_auto_now_add: bool = True

    @property
    def field(self):
        return self.model._meta.get_field(self.field_name)

    def test_field_type(self):
        assert isinstance(self.field, self.field_type)

    def test_is_null(self):
        assert self.field.null == self.is_null

    def test_is_blank(self):
        assert self.field.blank == self.is_blank

    def test_default_value(self):
        assert self.field.default == self.default_value

    def test_auto_now(self):
        if self.field.__class__ not in DATETIME_FIELDS:
            pytest.skip(
                f"{self.model.__name__}->{self.field_name} is not a date/time model type."
            )

        assert self.field.auto_now == self.is_auto_now

    def test_auto_now_add(self):
        if self.field.__class__ not in DATETIME_FIELDS:
            pytest.skip(
                f"{self.model.__name__}->{self.field_name} is not a date/time model type."
            )

        assert self.field.auto_now_add == self.is_auto_now_add